Urinary bladder wall gets streched when

Options

A. it filled with urine
B. it undergoes mictuition
C. it emptied
D. None

Answer

### Step-by-Step Solution:

1. **Understanding the Urinary Bladder**: The urinary bladder is a muscular sac that stores urine produced by the kidneys until it is ready to be expelled from the body.

2. **Filling of the Urinary Bladder**: The urinary bladder fills with urine that is transported from the kidneys through the ureters. As more urine accumulates, the bladder expands.

3. **Stretching of the Bladder Wall**: The wall of the urinary bladder is made up of smooth muscle and elastic tissue. As the bladder fills with urine, the pressure inside increases, causing the bladder wall to stretch.

4. **Micturition Process**: The act of releasing urine from the bladder is called micturition. This process is initiated when the bladder wall is stretched sufficiently, signaling the central nervous system (CNS) that it is time to empty the bladder.

5. **Voluntary Control**: The stretching of the bladder wall sends signals to the CNS, which then allows for voluntary control over the release of urine. When the person decides to urinate, the bladder contracts, and urine is expelled through the urethra.

6. **Conclusion**: Therefore, the urinary bladder wall gets stretched when it is filled with urine.

### Final Answer:
The urinary bladder wall gets stretched when it is filled with urine.

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